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101.
Sobolev G. A. Zakrzhevskaya N. A. Migunov I. N. Sobolev D. G. Boiko A. N. 《Izvestiya Physics of the Solid Earth》2020,56(3):291-315
Izvestiya, Physics of the Solid Earth - Abstract—The response of seismic noise in the minute range of periods to the strong magnetic storms is studied. The noise is analyzed from the records... 相似文献
102.
Mityaev A. S. Safonov O. G. Reutsky V. N. Izokh O. P. Varlamov D. A. Kozlovskii V. M. van Reenen D. D. Aranovich L. Y. 《Doklady Earth Sciences》2020,492(1):342-345
Doklady Earth Sciences - Data on the carbon and oxygen isotopic composition of carbonates from the rocks of the Giyani greenstone belt, Kaapvaal craton, South Africa are presented. This belt is... 相似文献
103.
Izvestiya, Atmospheric and Oceanic Physics - A low-parametric model of crop biomass dynamics using the data of satellite remote sensing of the underlying surface vegetation index and routine... 相似文献
104.
Doklady Earth Sciences - The evolution of the stress–strain state of the Earth’s crust in Southern California during the preparation period (from January 1, 2019 until August 15, 2019)... 相似文献
105.
Spiridonov E. A. Vinogradova O. Yu. 《Izvestiya Atmospheric and Oceanic Physics》2019,55(11):1814-1819
Izvestiya, Atmospheric and Oceanic Physics - A method for calculating of the Earth’s surface displacements due to atmospheric loading effect is presented. The load displacements are... 相似文献
106.
107.
Md. Nurul Haider Masahiko Nishimura Minoru Ijichi Ching-chia Yang Wataru Iwasaki Kazuhiro Kogure 《Journal of Oceanography》2018,74(2):197-207
Habitability is defined as an ability of an organism to inhabit different environments. Habitability of organisms, however, cannot be inferred from analyses such as a whole genome or community structures. A recently developed database, the MetaMetaDB, gives us information from what kind of environments one particular 16S rRNA sequence data has ever been obtained, and thus enables us to infer the habitability of the bacterium in question. In order to check the applicability of this database to study the habitability of aquatic bacteria, samples collected at two Naka River stations, one estuarine station from Naka River Estuary, two coastal stations at Oarai in Ibaraki Prefecture, Japan and one station in the Kuroshio Current of the western North Pacific were examined. The phylotypes were tracked against the MetaMetaDB and it was reasonably found that the low-salinity stations were dominated by sequences with “freshwater and groundwater”, “human” and “wastewater” habitat identities, while the high-salinity stations were dominated by those with a “marine” identity. The phylotypes of low-salinity stations with a particular habitat identity were absent or rare in the high-salinity stations and vice versa. The MetaMetaDB also showed that sequences of Cyanobacteria or related phylogenetic groups may be present in the human gut, as well as the probable distribution of the relatives (ancestors/descendants/siblings) of some bacteria. These overall findings proved that the MetaMetaDB is useful as a new tool to infer microbial habitability and it gives us new information on the possible origin and ecology of microorganisms in the environments. 相似文献
108.
109.
T. Vinutha V. U. M. Rao Bekele Getaneh Molla Mengesha 《Astrophysics and Space Science》2018,363(9):188
In this paper we have studied the anisotropic Kantowski-Sachs, locally rotationally symmetric (LRS) Bianchi type-I and LRS Bianchi type-III geometries filled with dark energy and one dimensional cosmic string in the Saez-Ballester theory of gravitation. To get physically valid solution we take hybrid expansion law of the average scale factor which is a product of power and exponential type of functions that results in time dependent deceleration parameter (\(q\)). The equation of state parameter of dark energy (\(\omega _{\mathit{de}}\)) has been discussed and we have observed that for the three models it crosses the phantom divide line (\(\omega _{\mathit{de}} = -1\)) and shows quintom like behavior. The density of dark energy (\(\rho _{\mathit{de}}\)) is an increasing function of redshift and remains positive throughout the evolution of the universe for the three models. Moreover in Kantowski-Sachs and LRS Bianchi type-I geometries the dark energy density dominates the string tension density (\(\lambda \)) and proper density (\(\rho \)) throughout the evolution of the universe. The physical and geometrical aspects of the statefinder parameters (\(r,s\)), squared speed of sound (\(v_{s}^{2} \)) and \(\omega _{\mathit{de}}\)–\(\omega ^{\prime }_{\mathit{de}}\) plane are also discussed. 相似文献
110.
Ayesha Anjum Mousumi Das Jayant Murthy S. B. Gudennavar Rajesh Gopal S. G. Bubbly 《Journal of Astrophysics and Astronomy》2018,39(5):61
We have classified a sample of 37,492 objects from SDSS into QSOs, galaxies and stars using photometric data over five wave bands (u, g, r, i and z) and UV GALEX data over two wave bands (near-UV and far-UV) based on a template fitting method. The advantage of this method of classification is that it does not require any spectroscopic data and hence the objects for which spectroscopic data is not available can also be studied using this technique. In this study, we have found that our method is consistent by spectroscopic methods given that their UV information is available. Our study shows that the UV colours are especially important for separating quasars and stars, as well as spiral and starburst galaxies. Thus it is evident that the UV bands play a crucial role in the classification and characterization of astronomical objects that emit over a wide range of wavelengths, but especially for those that are bright at UV. We have achieved the efficiency of 89% for the QSOs, 63% for the galaxies and 84% for the stars. This classification is also found to be in agreement with the emission line diagnostic diagrams. 相似文献